Electrochemical monitoring of binding between wheat germ agglutinin and cellohexose-modified magnetic microbeads

Abstract

An electrochemical method that uses glucose labeled with an electroactive compound was developed to evaluate the binding of wheat germ agglutinin (WGA) to cellohexose-modified magnetic microbeads. Cellohexose was attached to amino groups on the magnetic bead surface via formation of a Schiff's base. The labeled glucose acts as an electrochemical probe to monitor binding events between WGA and the cellohexose-modified beads. For a known quantity of cellohexose-modified beads, binding of WGA with cellohexose-modified beads was evaluated based on changes in electrochemical response of the labeled glucose. In particular, the peak current decreased as the concentration of WGA increased. Furthermore, the binding affinities of WGA for beads modified with four different cello-oligosaccharides were systematically compared using a voltammetric method.